1. Field
Embodiments relate to an error correction code circuit and a memory device including the same.
2. Description of the Related Art
A NAND flash memory is one of electrically erasable and programmable read only memories (EEPROMs). The NAND flash memory enables large amounts of data to be stored in a small chip area by using NAND cell units (NAND strings) in which a plurality of memory cells are serially connected.
In relation to a large capacity memory device such as the NAND flash memory, retained data disappear sometimes due to various causes. For example, due to degradation of a tunnel oxide layer according to several times of a rewrite operation, a memory cell loses data retaining characteristics while retaining data, and an error bit generation rate (error rate) tends to increase. In particular, in relation to the NAND flash memory, as a large capacity memory and a micronized manufacturing process are developed, the error rate tends to increase.
To handle this, an error correction code (ECC) circuit has been used to enhance performance of the NAND flash memory. Since this ECC circuit is mounted on-chip, a highly reliable memory may be provided.